Aegisub/aegisub/src/gl_text.cpp

389 lines
10 KiB
C++

// Copyright (c) 2007, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// Aegisub Project http://www.aegisub.org/
//
// $Id$
/// @file gl_text.cpp
/// @brief Create and render text using OpenGL
/// @ingroup video_output
///
#include "config.h"
#ifndef AGI_PRE
#include <wx/bitmap.h>
#include <wx/dcmemory.h>
#include <wx/image.h>
#include <algorithm>
#endif
#include "gl_text.h"
#include "utils.h"
#ifdef HAVE_OPENGL_GL_H
#include <OpenGL/gl.h>
#else
#include <GL/gl.h>
#endif
/// @class OpenGLTextGlyph
/// @brief Struct storing the information needed to draw a glyph
struct OpenGLTextGlyph {
wxString str; ///< String containing the glyph(s) this is for
int tex; ///< OpenGL texture to draw for this glyph
float x1; ///< Left x coordinate of this glyph in the containing texture
float x2; ///< Right x coordinate of this glyph in the containing texture
float y1; ///< Left y coordinate of this glyph in the containing texture
float y2; ///< Right y coordinate of this glyph in the containing texture
int w; ///< Width of the glyph in pixels
int h; ///< Height of the glyph in pixels
wxFont font; ///< Font used for this glyph
OpenGLTextGlyph(int value, wxFont const& font);
void Draw(float x, float y) const;
};
/// @class OpenGLTextTexture
/// @brief OpenGL texture which stores one or more glyphs as sprites
class OpenGLTextTexture {
int x; ///< Next x coordinate at which a glyph can be inserted
int y; ///< Next y coordinate at which a glyph can be inserted
int nextY; ///< Y coordinate of the next line; tracked due to that lines
///< are only as tall as needed to fit the glyphs in them
int width; ///< Width of the texture
int height; ///< Height of the texture
GLuint tex; ///< The texture
/// Insert the glyph into this texture at the current coordinates
void Insert(OpenGLTextGlyph &glyph);
public:
/// @brief Try to insert a glyph into this texture
/// @param[in][out] glyph Texture to insert
/// @return Was the texture successfully added?
bool TryToInsert(OpenGLTextGlyph &glyph);
OpenGLTextTexture(OpenGLTextGlyph &glyph);
~OpenGLTextTexture();
};
OpenGLText::OpenGLText()
: r(1.f)
, g(1.f)
, b(1.f)
, a(1.f)
, lineHeight(0)
, fontSize(0)
, fontBold(false)
, fontItalics(false)
{
}
OpenGLText::~OpenGLText() {
}
void OpenGLText::SetFont(wxString face,int size,bool bold,bool italics) {
// No change required
if (size == fontSize && face == fontFace && bold == fontBold && italics == fontItalics) return;
// Set font
fontFace = face;
fontSize = size;
fontBold = bold;
fontItalics = italics;
font.SetFaceName(fontFace);
font.SetPointSize(size);
font.SetWeight(bold ? wxFONTWEIGHT_BOLD : wxFONTWEIGHT_NORMAL);
// Delete all old data
textures.clear();
glyphs.clear();
}
void OpenGLText::SetColour(wxColour col,float alpha) {
r = col.Red() / 255.f;
g = col.Green() / 255.f;
b = col.Blue() / 255.f;
a = alpha;
}
void OpenGLText::Print(const wxString &text,int x,int y) {
glEnable(GL_BLEND);
glEnable(GL_TEXTURE_2D);
glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
// Draw border
glColor4f(0.0f,0.0f,0.0f,1.0f);
DrawString(text,x-1,y);
DrawString(text,x+1,y);
DrawString(text,x,y-1);
DrawString(text,x,y+1);
// Draw primary string
glColor4f(r,g,b,a);
DrawString(text,x,y);
// Disable blend
glDisable(GL_TEXTURE_2D);
glDisable(GL_BLEND);
}
void OpenGLText::DrawString(const wxString &text,int x,int y) {
size_t len = text.Length();
lineHeight = 0;
int dx=x,dy=y;
for (size_t i=0;i<len;i++) {
int curChar = text[i];
// Handle carriage returns
if (curChar == '\n') {
dx = x;
dy += lineHeight;
}
// Handle normal glyphs
else {
OpenGLTextGlyph const& glyph = GetGlyph(curChar);
glyph.Draw(dx,dy);
dx += glyph.w;
if (glyph.h > lineHeight) lineHeight = glyph.h;
}
}
}
void OpenGLText::GetExtent(wxString const& text, int &w, int &h) {
size_t len = text.Length();
lineHeight = 0;
int dx=0,dy=0;
w = 0;
h = 0;
// Simulate drawing of string
for (size_t i=0;i<len;i++) {
// Get current character
int curChar = text[i];
// Handle carriage returns
if (curChar == '\n') {
if (dx > w) w = dx;
dx = 0;
dy += lineHeight;
lineHeight = 0;
}
// Handle normal glyphs
else {
OpenGLTextGlyph const& glyph = GetGlyph(curChar);
dx += glyph.w;
if (glyph.h > lineHeight) lineHeight = glyph.h;
}
}
// Return results
if (dx > w) w = dx;
h = dy+lineHeight;
}
OpenGLTextGlyph const& OpenGLText::GetGlyph(int i) {
glyphMap::iterator res = glyphs.find(i);
if (res != glyphs.end()) return res->second;
return CreateGlyph(i);
}
OpenGLTextGlyph const& OpenGLText::CreateGlyph(int n) {
OpenGLTextGlyph &glyph = glyphs.insert(std::make_pair(n, OpenGLTextGlyph(n, font))).first->second;
// Insert into some texture
bool ok = false;
for (unsigned int i=0;i<textures.size();i++) {
if (textures[i]->TryToInsert(glyph)) {
ok = true;
break;
}
}
// No texture could fit it, create a new one
if (!ok) {
textures.push_back(std::tr1::shared_ptr<OpenGLTextTexture>(new OpenGLTextTexture(glyph)));
}
return glyph;
}
/// @brief Texture constructor
/// @param w
/// @param h
OpenGLTextTexture::OpenGLTextTexture(OpenGLTextGlyph &glyph) {
x = y = nextY = 0;
width = std::max(SmallestPowerOf2(glyph.w), 64);
height = std::max(SmallestPowerOf2(glyph.h), 64);
width = height = std::max(width, height);
tex = 0;
// Generate and bind
glGenTextures(1, &tex);
glBindTexture(GL_TEXTURE_2D, tex);
// Texture parameters
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP);
// Allocate texture
glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA8,width,height,0,GL_ALPHA,GL_UNSIGNED_BYTE,NULL);
if (glGetError()) throw "Internal OpenGL text renderer error: Could not allocate Text Texture";
TryToInsert(glyph);
}
OpenGLTextTexture::~OpenGLTextTexture() {
if (tex) glDeleteTextures(1, &tex);
}
/// @brief Can fit a glyph in it?
/// @param glyph
/// @return
bool OpenGLTextTexture::TryToInsert(OpenGLTextGlyph &glyph) {
int w = glyph.w;
int h = glyph.h;
if (w > width) return false;
if (y+h > height) return false;
// Can fit in this row?
if (x + w < width) {
Insert(glyph);
x += w;
if (y+h > nextY) nextY = y+h;
return true;
}
// Can fit the next row?
else {
if (nextY+h > height) return false;
x = 0;
y = nextY;
Insert(glyph);
x += w;
nextY = y+h;
return true;
}
}
/// @brief Insert
/// @param glyph
void OpenGLTextTexture::Insert(OpenGLTextGlyph &glyph) {
int w = glyph.w;
int h = glyph.h;
// Fill glyph structure
glyph.x1 = float(x)/width;
glyph.y1 = float(y)/height;
glyph.x2 = float(x+w)/width;
glyph.y2 = float(y+h)/height;
glyph.tex = tex;
// Create bitmap and bind it to a DC
wxBitmap bmp(w + (w & 1), h + (h & 1),24);
wxMemoryDC dc(bmp);
// Draw text and convert to image
dc.SetBackground(wxBrush(wxColour(0,0,0)));
dc.Clear();
dc.SetFont(glyph.font);
dc.SetTextForeground(wxColour(255,255,255));
dc.DrawText(glyph.str,0,0);
wxImage img = bmp.ConvertToImage();
// Convert to alpha
int imgw = img.GetWidth();
int imgh = img.GetHeight();
size_t len = imgw*imgh;
const unsigned char *src = img.GetData();
const unsigned char *read = src;
std::vector<unsigned char> alpha(len * 2, 255);
unsigned char *write = &alpha[1];
for (size_t i=0;i<len;i++) {
*write = *read;
write += 2;
read += 3;
}
// Upload image to video memory
glBindTexture(GL_TEXTURE_2D, tex);
glTexSubImage2D(GL_TEXTURE_2D,0,x,y,imgw,imgh,GL_LUMINANCE_ALPHA,GL_UNSIGNED_BYTE,&alpha[0]);
if (glGetError()) throw "Internal OpenGL text renderer error: Error uploading glyph data to video memory.";
}
/// Draw a glyph at (x,y)
void OpenGLTextGlyph::Draw(float x, float y) const {
glBindTexture(GL_TEXTURE_2D, tex);
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
float tex_coords[] = {
x1, y1,
x1, y2,
x2, y2,
x2, y1
};
float vert_coords[] = {
x, y,
x, y + h,
x + w, y + h,
x + w, y
};
glVertexPointer(2, GL_FLOAT, 0, vert_coords);
glTexCoordPointer(2, GL_FLOAT, 0, tex_coords);
glDrawArrays(GL_QUADS, 0, 4);
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
}
/// @brief DOCME
OpenGLTextGlyph::OpenGLTextGlyph(int value, wxFont const& font)
: str(wxChar(value))
, font(font)
{
wxCoord desc,lead;
wxBitmap tempBmp(32, 32, 24);
wxMemoryDC dc(tempBmp);
dc.SetFont(font);
dc.GetTextExtent(str,&w,&h,&desc,&lead);
}